Downhole apparatus

Abstract

Apparatus for use in setting packers and other fluid actuated devices includes a tubular body (222), a valve (228) for controlling the flow of well fluid through a port (234) in the body (222) and a valve actuator (224) mounted on the body (222) and movable relative thereto, to open the valve (228) by application of well fluid pressure. The well fluid may flow through the open valve (228) to set a packer or actuate a device.

What is claimed is: 
     
       1. Downhole completion apparatus for mounting on a string below a packer in combination with a fluid pressure actuated device, the apparatus comprising: a tubular body defining a bore;   means for sealing the body bore;   a valve for controlling the flow of well fluid through a first port in the tubular body, the port being in communication with said fluid pressure actuated device; and   a valve actuator mounted on the body and movable relative thereto, to open the valve, on application of well fluid pressure to the body bore above the sealing means, to permit actuation of said fluid pressure actuated device.   
     
     
       2. The apparatus of claim 1 wherein the actuator includes an axially slidable sleeve, the sleeve being a valve member and defining a circulating port for selectively providing fluid communication with a further port in the body, to permit fluid circulation between the bore and an annulus defined between the body and a surrounding bore wall. 
     
     
       3. The apparatus of claim 1 in which the fluid actuated device is a packer. 
     
     
       4. The apparatus of claim 2 wherein the sleeve is biased towards a first position by a spring. 
     
     
       5. The apparatus of claim 2 wherein the sleeve defines a piston in fluid communication with the body bore, whereby an increase in the bore pressure is communicated to the piston and tends to move the piston towards a second position. 
     
     
       6. The apparatus of claim 2 wherein the actuator sleeve is initially positioned on the body to permit circulation through said further body port, application of fluid pressure moving the sleeve to a second position to close the port, and means being provided for biasing the sleeve to return to the initial position. 
     
     
       7. The apparatus of claim 1 including two or more valves for selectively controlling well fluid communication to a plurality of fluid actuated devices. 
     
     
       8. The apparatus of claim 1 in combination with one of a flow sleeve and an isolation valve. 
     
     
       9. Downhole apparatus for location in a drilled bore, the apparatus comprising: a tubular body defining a bore;   a fluid pressure actuated device mounted on the body;   a valve for controlling flow of well fluid through a first port in the tubular body to control actuation of the fluid pressure actuated device; and   a valve actuator mounted on the body and movable relative thereto to open the valve on application of well fluid pressure, the valve actuator including an axially slidable sleeve defining a circulating port for selectively providing fluid communication with a further port in the body, to permit passage of fluid between the body bore and an annulus defined between the body and the wall of the drilled bore.   
     
     
       10. Downhole completion apparatus for mounting on a string below a packer, the apparatus comprising: a tubular body defining a bore;   means for sealing the body bore;   a valve for controlling the flow of well fluid through a first port in the tubular body, the port being in communication with a fluid pressure actuated device; and   a valve actuator mounted on the body and movable relative thereto, to open the valve, on application of well fluid pressure to the body bore above the sealing means,   the actuator including an axially slidable sleeve, the sleeve being a valve member and defining a circulating port for selectively providing fluid communication with a further port in the body, to permit fluid circulation between the bore and an annulus defined between the body and a surrounding bore wall, the actuator sleeve being initially positioned on the body to permit circulation through said further body port, application of fluid pressure moving the sleeve to a second position to close the port, and means being provided for biasing the sleeve to return to the initial position,     wherein means is provided for restricting return movement of the sleeve from the second position such that the further body port remains closed after a predetermined number of pressure cycles.   
     
     
       11. Downhole apparatus for location in a drilled bore, the apparatus comprising: a tubular body defining a bore;   a fluid pressure actuated device mounted on the body;   a valve for controlling flow of well fluid through a first port in the tubular body to control actuation of the fluid pressure actuated device,   the actuator including an axially slidable sleeve, the sleeve being a valve member and defining a circulating port for selectively providing fluid communication with a further port in the body, to permit fluid circulation between the bore and an annulus defined between the body and a surrounding bore wall,   wherein the actuator includes a ratchet assembly having a ratch member which advances one step relative to the body towards an actuating position with each pressure cycle.   
     
     
       12. The apparatus of claim 11 wherein the ratchet assembly is provided between the body and the sleeve and the ratch member is advanced axially along the body. 
     
     
       13. The apparatus of claim 12 wherein the ratch member is located between ratchet tracks defined by the sleeve and body. 
     
     
       14. Downhole completion apparatus for mounting on a string below a packer, the apparatus comprising: a tubular body defining a bore;   means for sealing the body bore;   a valve for controlling the flow of well fluid through a first port in the tubular body, the port being in communication with a fluid pressure actuated device; and   a valve actuator mounted on the body and movable relative thereto, to open the valve, on application of well fluid pressure to the body bore above the sealing means,   wherein the valve is in the form of a shuttle valve.   
     
     
       15. A method of selectively actuating a pressure actuated downhole device mounted on a tubular body defining a bore and mounted on a string below a packer, the method comprising: sealing the body bore below the packer;   providing a valve for controlling flow of well fluid through a port in the tubular body, the port being in communication with a fluid pressure actuated device;   providing a valve actuator on the tubular body; and   applying well fluid pressure to the body bore to move the actuator to open the valve and permit communication of said fluid pressure to said device to actuate said device.   
     
     
       16. The method of claim 15 wherein the pressure actuated device is the packer and the packer communicates with the port via a control line. 
     
     
       17. The method of claim 16 wherein the valve is located below the packer. 
     
     
       18. A method of (i) selectively actuating a pressure actuated downhole device mounted on a tubular body defining a bore and (ii) permitting fluid circulation between the body bore and an annulus defined between the body and the wall of a drilled bore, the method comprising: providing a valve for controlling flow of well fluid through a port in the tubular body, the port being in communication with a fluid pressure actuated device;   providing a valve actuator on the tubular body, the valve actuator including an axially slidable sleeve defining a circulating port for selectively providing fluid communication with a further port in the body;   (i) applying well fluid pressure to the actuator to open said valve and actuate said device; and   (ii) applying well fluid pressure to the actuator to move the sleeve and permit fluid circulation between the body bore and an annulus defined between the body and the wall of the drilled bore via said circulating port and said further port in the body.